Fix for a potential data race condition

modules/objdetect/src/detection_based_tracker.cpp

@@ -286,6 +286,13 @@ void* cv::workcycleObjectDetectorFunction(void* p)
     try{
         ((cv::DetectionBasedTracker::SeparateDetectionWork*)p)->lock();
         ((cv::DetectionBasedTracker::SeparateDetectionWork*)p)->stateThread = cv::DetectionBasedTracker::SeparateDetectionWork::STATE_THREAD_STOPPED;
+        ((cv::DetectionBasedTracker::SeparateDetectionWork*)p)->isObjectDetectingReady=false;
+        ((cv::DetectionBasedTracker::SeparateDetectionWork*)p)->shouldObjectDetectingResultsBeForgot=false;
+#ifdef USE_STD_THREADS
+        objectDetectorThreadStartStop.notify_one();
+#else
+    pthread_cond_signal(&objectDetectorThreadStartStop);
+#endif
         ((cv::DetectionBasedTracker::SeparateDetectionWork*)p)->unlock();
     } catch(...) {
         LOGE0("DetectionBasedTracker: workcycleObjectDetectorFunction: ERROR concerning pointer, received as the function parameter");
@@ -439,25 +446,6 @@ void cv::DetectionBasedTracker::SeparateDetectionWork::workcycleObjectDetector()
         objects.clear();
     }// while(isWorking())
 
-#ifdef USE_STD_THREADS
-    mtx_lock.lock();
-#else
-    pthread_mutex_lock(&mutex);
-#endif
-
-    stateThread=STATE_THREAD_STOPPED;
-
-    isObjectDetectingReady=false;
-    shouldObjectDetectingResultsBeForgot=false;
-
-#ifdef USE_STD_THREADS
-    objectDetectorThreadStartStop.notify_one();
-    mtx_lock.unlock();
-#else
-    pthread_cond_signal(&objectDetectorThreadStartStop);
-    pthread_mutex_unlock(&mutex);
-#endif
-
     LOGI("DetectionBasedTracker::SeparateDetectionWork::workcycleObjectDetector: Returning");
 }